Madisonville, KentuckySeptember 1962

On September 11, 1962, police and Civil Defense officials in Madisonville, Kentucky received reports of a strange substance falling from the sky. Witnesses described it as resembling spun glass or gossamer, falling in large quantities near a residential area. The observation lasted from approximately 0939 (9:39 a.m.) until 1100 (11:00 a.m.), more than an hour of continuous activity.

State police were dispatched to investigate. When they arrived, they found fibers and particle-like material coating the ground and still descending slowly. Witnesses who had gathered the material reported seeing spiders clinging to pieces of it. The Air Force was contacted for guidance, and officials suggested three possible explanations: chemical residue from cloud seeding operations, industrial discharge from a defective filter, or gossamer created by migrating spiders.

Follow-up investigation quickly eliminated the first two possibilities. Witnesses were recontacted and confirmed that they had indeed observed spiders among the floating material. Local biology students and professors at nearby institutions had also witnessed the phenomenon and confirmed the presence of spiders. The state police concluded in their report that the substance was gossamer, a fine, silky fiber spiders produce and release during migration, which would have floated naturally with the 15 mile per hour ground wind observed that day. The yearly migration of spiders and their production of gossamer is well-documented as a normal seasonal occurrence.

The Air Force classified the sighting as unidentified in its initial assessment, though the investigative record indicates that the most probable explanation was the natural phenomenon of spider migration and gossamer dispersal. The full case file, comprising 11 pages as held by the National Archives, is reproduced below.